Engineering Calculators Catalog
Browse our comprehensive suite of verified calculation engines and upcoming engineering workflows.
RO Recovery Calculator
Calculate RO permeate and concentrate flow from feed flow and system recovery rate.
Recovery (%) = (Permeate Flow / Feed Flow) × 100 RO Salt Rejection Calculator
Calculate membrane salt rejection percentage from feed and permeate TDS concentrations.
Rejection (%) = (1 - (Cp / Cf)) × 100 RO Salt Passage Calculator
Determine salt passage percentage through RO membranes and verify complementary rejection balance.
Passage (%) = (Cp / Cf) × 100 RO Permeate TDS Calculator
Project expected permeate total dissolved solids based on feed water salinity and rejection specs.
Cp = Cf × (1 - R / 100) RO Concentrate Flow Calculator
Compute brine/reject flow rates and volumetric stream balances for disposal or ZLD design.
Qc = Qf - Qp = Qf × (1 - Y / 100) RO Osmotic Pressure Calculator
Estimate RO feed osmotic pressure using a simplified van’t Hoff model from TDS, temperature, and solute properties.
π = i × C × R × T RO Design Studio
Build a preliminary RO system design with feed inputs, staging, custom membrane data, sequential element estimates, balances, and warnings.
Q = A × S × (ΔP − Δπ) RO Mass Balance Calculator
Simplified TDS-based dissolved-solids balance for RO feed, permeate, and concentrate flow and quality checks.
Qf · Cf = Qp · Cp + Qc · Cc RO Scaling Risk & Pretreatment Analysis
Screen CaCO3 scaling risk in RO feed and concentrate using the Langelier Saturation Index (ASTM D3739) and the Stiff & Davis Stability Index (S&DSI) for high-TDS and seawater feeds.
LSI = pH − pHS · S&DSI = pH − pCa − pAlk − K RO Membrane Sizing Calculator
Calculate required number of membrane elements and pressure vessels from design flux.
RO Energy & Specific Power Calculator
Determine specific energy consumption (kWh/m³) based on operating pressure and pump efficiency.
RO Operating Cost (OPEX) & SEC Calculator
Estimate RO operating expenditure: pumping energy (specific energy consumption), chemical cleaning, antiscalant, and membrane replacement.
SEC = P_feed × Q_f/(η_pump·Q_p) · OPEX = Σ (energy + chemical + membrane + maintenance) RO Concentration Factor & Salt Load Calculator
Compute RO water concentration factor (CF = 1/(1−Y)) and the salt load carried to concentrate for scaling and disposal analysis.
CF = 1 / (1 − Y) · Salt Load = Q_f × C_f × Y_loading RO Feed Pressure & Specific Energy Calculator
Estimate required RO feed pressure (permeate osmotic gap + net driving pressure) and specific energy consumption with optional energy recovery.
P_feed ≈ Δπ + (J × 100/B·SCP factor) + ΔP_friction RO Antiscalant & Chemical Dosing Calculator
Calculate antiscalant (or chemical) dosing rate and 100% active-equivalent flow from dose concentration and product strength.
Dose Flow = Q_feed × Dose_ppm / (C_prod × 100) (SG-adjusted) RO Membrane & Vessel Element Count Calculator
Calculate number of RO membrane elements and pressure vessels from permeate flow, design flux, and element area.
Elements = Q_p / (Flux × A_element) · Vessels = ⌈Elements / Elements per Vessel⌉ Pump Power Calculator
Calculate hydraulic power, shaft power, and motor electrical power from head and flow rate.
HPump = ρ × g × Q × H / η Engineering Unit & Water Quality Converter
Convert flow rates and TDS concentration units (mg/L ↔ ppm) using the Site canonical unit engines (m³/day internal).
Canonical flow unit = m³/day · 1 mg/L ≈ 1 ppm (dilute aqueous) Pipe Flow & Friction Loss Calculator
Determine pipe velocity, friction head loss, and pressure drop via Darcy-Weisbach or Hazen-Williams.
v = Q / A · hf = 10.67 × L × Q^1.852 / (C^1.852 × D^4.871) Open Channel Flow (Manning′) Calculator
Compute open-channel velocity and discharge with Manning’s equation for trapezoidal, rectangular, and circular channels.
v = (1/n) × R^(2/3) × S^(1/2) · Q = v × A Pipe Flow Velocity & Sizing Calculator
Size a pipe to carry a target flow within a recommended velocity range, or check velocity for a given diameter.
D = √(4Q / (π·v)) · v = Q / A Reynolds Number & Flow Regime Calculator
Calculate Reynolds number for pipe flow and classify the flow regime (laminar / transitional / turbulent).
Re = ρ·v·D / μ Pipe Pressure Drop (Darcy–Weisbach) Calculator
Compute pipe head loss and pressure drop with the Darcy–Weisbach equation, solving the Colebrook friction factor.
hf = f × (L/D) × (v²/2g) · f via Colebrook-White Pump Head / Total Dynamic Head Calculator
Compose total dynamic head from static lift, friction losses, minor losses, and residual pressure.
TDH = H_stat + h_friction + h_minor + h_residual Pressure & Head Unit Converter
Convert pressure and head units: bar, kPa, MPa, psi, m H₂O, ft H₂O, and atmospheres.
1 bar = 100 kPa = 14.5038 psi = 10.197 m H₂O Volumetric → Mass Flow Converter
Convert volumetric flow to mass flow (and reverse) using fluid density, with common water/TDS basis.
ṁ = ρ × Q · Q = ṁ / ρ Water Tank Storage Calculator
Size cylindrical and rectangular water storage tanks from dimensions or daily demand and residence time.
V = π/4 × D² × H · V = L × W × H Water Demand & Flow Requirement Calculator
Estimate community or facility water demand (domestic, commercial, fire) and the design flow requirement for supply and storage sizing.
Q_design = P · q · peakFactor · Q_avg = V_daily / 86400 Tank Fill Time & Filling Rate Calculator
Calculate the time to fill a storage tank from a known filling rate, or the filling rate required to meet a target time.
t = V / Q · Q = V / t Concrete Volume Calculator
Calculate total concrete volume and pre-mixed bag quantities for slabs, footings, and curbs.
V = L × W × H · V_ready = V × (1 + wastage/100) · Bags = ceil(V_ready / 0.033) Slab Concrete Volume Calculator
Determine rectangular and irregular slab volumes with wastage margins.
Footing & Foundation Volume Calculator
Calculate concrete required for spread (pad) footings and strip footings, per-footing and total volumes with ready-mix allowance.
V = L × W × D × n · V_ready = V_total × (1 + wastage/100) Column Concrete Volume Calculator
Accurate concrete requirements for round, square, and rectangular structural columns.
V = A × H × n · A = (π/4)d² round, b×b square, w×d rectangular Concrete Mix Design Calculator
Compute per-batch and per-cubic-meter quantities of cement, sand, aggregate, and water from a mix ratio.
V_dry = V × 1.54 · M_mat = V_dry × (ratio / Σ ratios) · Water = w/c × cement mass Rebar Weight Calculator
Compute theoretical rebar steel weight per meter and total tonnage from bar diameter and lengths.
W = d² / 162 (kg/m, d in mm) Rebar Quantity Takeoff Calculator
Estimate number of reinforcement bars required for slabs and walls based on spacing and cover.
Bars = ⌊(L - 2c) / s⌋ + 1 Masonry & Block Quantity Calculator
Estimate block quantities, mortar volume, and wall material takeoff from wall geometry and joint thickness.
N = ceil(L/courseW) × ceil(H/courseH) · Mortar = V_bed + V_perp Steel Weight Calculator
Compute structural steel and reinforcement weight for plates, bars, pipes, and standard sections using steel density.
W = V × ρ_steel (ρ ≈ 7,850 kg/m³) Construction Material Quantity Takeoff Calculator
Quantity takeoff for bulk construction materials with wastage: aggregate, sand, cement, and general volume-mass conversions.
Q = V × (1 + wastage/100) · m = Q × ρ Construction Cost Escalation & Scenario Calculator
Escalate a base construction cost to a target date with a user-supplied annual rate and compare alternative escalation scenarios.
C(t) = C₀ × (1 + r/100)^n · n = days ÷ 365.25 Embodied Carbon Screening & Comparison Calculator
Compare two design options on screened embodied carbon using user-supplied emission factors, with breakdown and per-m² intensity.
kgCO₂e = Σ (material quantity × user factor) · intensity = kgCO₂e / area Stormwater Runoff (Rational Method) Calculator
Estimate peak stormwater runoff with the Rational Method (Q = C·i·A) for drainage design and storm sewer sizing.
Q = 2.78 × C × i × A (L/s, A in ha, i in mm/h) Trench Excavation & Bedding Calculator
Calculate trench excavation volume, pipe displacement, bedding material quantity, and backfill volumes.
V_trench = A × L · Backfill = V_trench − V_pipe − V_bedding Earthwork Cut and Fill Calculator
Estimate site earth movement balance and bulk haulage volumes with swell and shrinkage factors.
Net = ΣCut − ΣFill (bank m³) · Export = Net × (1 + swell/100) · Import = −Net × (1 + shrink/100) No matching calculators found
Try searching for terms like "RO", "permeate", "flow", "concrete", or "rebar".